Giant enhanced stability of the quantum electron solid from a weakened electron-electron interaction in double-layer MoS 2

The melting temperature of the quantum electron solid in double-layer two-dimensional MoS2 stacked on opposite sides of a thin layer of BN is larger than previous single-layer results in Si-MOSFETs and bilayer estimates by four orders of magnitude. This giant enhancement of the stability of the solid comes from a shear modulus μ that is an order of magnitude larger than expected and comes from a weakened electron-electron interaction due to the screening by the polarization charges at the interfaces of the experimental structure. We found that the short-range part of the interelectron Coulomb potential actually provides for a negative contribution to μ and makes the lattice less stable. The weakening of this short-range contribution enhances μ by an order of magnitude. This large μ, together with a larger energy scale e2/ab for a smaller Bohr radius ab for the experimental structure, leads to a high melting temperature and makes possible using the structure as a practical logic device. Our understanding of this phenomenon guides us in optimizing its design. The large melting temperature and the small zero-temperature critical density agrees with experimental results extracted from the density and temperature dependence of the Coulomb drag resistance.
This article was originally published in Physical Review B. The version of record is available at: ©2024 American Physical Society
Chui, S. T., Meizhen Huang, Zefei Wu, and Ning Wang. “Giant Enhanced Stability of the Quantum Electron Solid from a Weakened Electron-Electron Interaction in Double-Layer MoS 2.” Physical Review B 109, no. 16 (April 5, 2024): 165412.